Human Uses of Energy

2. As the sun heats the atmosphere, air moves around and ______ turbines change that motion to electrical energy.
5. Layers of this is formed when plants died and fell into the water and decomposed.
6. ______ fuels are materials that formed as ancient plants and animals decayed underground.
7. We also use plants to produce chemical fuels, such as __________.
11. ____________ gas is a fossil fuel that occurs in the gas state.
12. Heat energy obtained from beneath Earth's surface is ______________ energy.
13. _____ can be used to make a renewable fuel called ethanol.
15. The making of coal takes more than 10 _________ years.
16. As water flows through openings in a dam, it turns a _________, which then causes a generator to produce electricity.
17. This is found in underground rocks and used by most nuclear power plants.

1. ____________ relies on flowing water to create motion, such as a wheel turning to create energy.
3. Solar energy is a ______________ source since the sun does not run out -- at least for the next few billion years!
4. Earth and pressure from soil and rock change peat into this.
8. Burning fossil fuels can have a harmful _________ on the environment causing air pollution and acidic lakes.
9. A ________ stores chemical energy and can convert that energy into electrical energy.
10. This is a liquid fossil fuel formed by the decay of ancient plants and animals.
14. _______ energy is when plant materials are burned as firewood or changed into liquid fuels.